Sunday, July 19, 2009

Role of sun over-emphasised in melanoma skin cancers

But suntanning does give you wrinkles! From what I have seen elsewhere, the advice below is rather confused, however. Fair skin certainly gives you more cancers, but BCCs and SCCs rather than melanomas -- and it is melanomas that are the dangerous ones. Melanomas are actually quite rare among very fair-skinned people, from my reading in the matter. It is people who tan well who get the melanomas

WARNINGS that too much time spent in the sun can lead to the most deadly form of skin cancer have been over-emphasised, a controversial study has claimed. It found that, although sunbathing is a risk factor, the number of moles on a person's skin is the most important indicator of whether they will go on to develop melanoma. The scientists also identified two genes that dictate how many moles someone will have, and their risk of getting skin cancer.

The research, published in the journal Nature Genetics, is likely to reopen the debate over whether official health warnings about avoiding the sun are overstated and too general. The study's authors said such warnings would be more useful if they focused on those most at risk – namely anyone with more than 100 moles on their body, redheads and people with fair skin and taught them how to check their moles for changes in shape, size or colour.

Tim Spector, professor of genetic epidemiology at King's College London, and one of the new study's authors, said: "The number of moles you have is one of the strongest risk factors for melanoma – stronger even than sunshine."

Dr Veronique Bataille, a dermatologist at West Hertfordshire NHS Trust, added: "You often read that nearly all melanomas are caused by sunshine, which is not supported by the evidence. "Let's keep sunshine in the picture because it does make you age and causes you wrinkles. But let's move away from scaring people by saying they are going to die because they go in the sun."


The dangerous "Homeopathic" loophole

Homeopathic remedies, except when people rely on them to treat serious conditions, are usually safe as water--which they actually are. But sometimes they contain dangerous ingredients which are released on a unsuspecting public with little or no testing

The Food and Drug Administration (FDA) has caught itself in a trap of precedent and logic that should force it, finally, to regulate homeopathic products. FDA regulations require that drugs and treatments be “scientifically proven safe and effective.” Homeopathic remedies, except when people rely on them to treat serious conditions, are usually safe as water—which they actually are. Some homeopaths claim that shaking and serial dilutions—even to the point that not one molecule of the “active” ingredient remains—create a “memory” of the long-gone ingredient. So far, though, the FDA has ignored the multi-million dollar fraud. After all, what’s the harm?

Well, one harm, according to hundreds of people and dozens of lawsuits, is that some of Matrixx Initiatives’ homeopathic Zicam cold “treatments” cause anosmia—the loss of smell, a sense necessary both to enjoy a summer day and to detect gas leaks, fires and spoiled food.

Rather than the usual homeopathic magic water, some Zicam products contain pharmaceutically significant amounts of zinc, which was shown in the 1930s to cause anosmia when used intranasally. Some Zicam homeopathics also include an unspecified amount of benzalkonium chloride, which “disrupts signaling between molecules, a mechanism that could allow it to have widespread unanticipated effects,” says Peter Montague of Rachel’s Democracy and Health News. The U.S. Material Safety Data Sheet lists it as a hazardous, potentially mutagenic chemical; Canada bars it from products “applied to mucous membranes.”

But the giant regulatory loophole that is homeopathy allowed Matrixx, either by accident or design, to slap on the label “homeopathic,” slip under the regulatory wire and sell 1 billion doses of untested Zicam. Despite Zicam’s decade on the market and numerous lawsuits, the National Center for Homeopathy never condemned the mislabeling.

Under the Obama administration, the FDA requested that Matrixx recall a number of Zicam intranasal products. On June 16, the FDA warned, “Because they are not generally recognized as safe and effective for their labeled uses, these products [must undergo] well-controlled clinical investigations … regardless of their homeopathic status [before re-marketing.]”

While there is conflicting evidence that oral zinc shortens colds, it likely does little harm. The FDA, however, found Zicam ineffective, thereby fitting it under the agency’s definition of “health fraud.” It also ruled that Zicam’s moneymaking innovation of delivering the chemical into the nose rendered it unsafe.

The Zicam recall followed an earlier tough (and witty) FDA ruling that if General Mills continued to claim whole-grain Cheerios reduces cholesterol, the cereal would be regulated as a drug. In June, the agency made Bayer withdraw claims that One A Day for Men “supports prostate health.”

In addition to the 130 anosmia reports received by the FDA, Matrixx failed to notify the agency of more than 800 Zicam-related complaints. Furthermore, since Zicam was labeled for use by children, a class of underage victims may have gone unnoticed.

Nonetheless, Matrixx CEO William Helmut called the Zicam recall “a complete surprise.” And it is an expensive one. The zinc-based nasal products comprised 40 percent of Matrixx’s $112-million sales last year. The Scottsdale, Ariz., firm used some of the profits to pay $12 million in 2006 to settle hundreds of lawsuits by Zicam users claiming anosmia, plus $4 to $6 million in annual legal costs. Matrixx is currently under investigation by the Securities and Exchange Commission over its handling of the FDA warning and by the Federal Trade Commission for deceptive marketing.

Questionable marketing may come naturally to Zicam through its co-founders Robert Steven Davison and Charles B. Hensley. Davidson got his Ph.D. from an unaccredited, now-defunct diploma mill in Spain. Hensley, who holds the Zicam patents, got a warning letter from the FDA about the online sale of an unapproved drug that his current company, PRB Pharmaceuticals, claims treats bird flu and SARS. And the Washington Post reported: “Hensley previously developed a weight-loss remedy that involves sniffing ‘specially developed aromas.’ “

Meanwhile, Zicam users, who can no longer smell a rat, might develop a nose for bullshit and discover that sometimes the only thing worse than homeopathic products that have no effect are the ones that do. 


Unintended use of drug restores hearing

Obama's FDA will now do its best to prevent this use of the drug -- because it is "off label"

It was the honeyed drawl of her professor that first pierced the silence enveloping Edith Garrett for an entire year, since the day she had lost her hearing. But she dismissed it, thinking she was just having a good day. That was until she was woken from her nap later that November afternoon by a racket from a neighbor’s apartment. “I said, ‘What is that?’ My roommates looked at me, and they said: ‘It’s the dog barking downstairs. It’s been there since August when we moved in,’ ’’ Garrett recalled.

Today, Garrett’s hearing is near-perfect in one ear, her rare neurological ailment treated by a drug called Avastin. But the wonder here isn’t simply that her hearing has been restored. The real wonder is how.

Garrett’s recovery, highlighted yesterday by researchers at Massachusetts General Hospital, represents a powerful tale of scientific discovery that illustrates how millions of dollars in spending and years of research into a drug - in this instance, Avastin, approved to treat late-stage colon, breast, and lung cancers - can yield a treatment for seemingly unrelated diseases.

For rare conditions, finding unintended uses for off-the-shelf drugs is often the best approach - saving time and money - because the potential financial payoff for a new medication is too little to attract interest from big drug companies.

The beneficiary in this case was Garrett. As a 19-year-old college student, she was diagnosed with neurofibromatosis type 2, which causes tumors to sprout inside the brain. Traditionally, as the tumors engulf nerves that regulate hearing, balance, swallowing, and other vital functions, patients are left with two options: surgery and radiation, both with worrisome complications.

Mass. General researchers’ findings on the unexpected value of Avastin, chronicled online yesterday by the New England Journal of Medicine, are preliminary. Researchers warn the drug is not a cure for the condition, most often diagnosed when people reach their 20s and estimated to afflict about 12,000 Americans. But it offers a shard of promise for patients often left hopeless by the rarity of their disease. “We really felt we stood on the shoulders of the oncology community,’’ said Dr. Scott Plotkin , director of Mass. General’s Neurofibromatosis Clinic and lead author of the study. “Our goal was to build on the scientific successes to date and not to have to go back to square one.’’

Neurofibromatosis type 2 - known in medical shorthand as NF-2 - typically arrives with quiet stealth. During high school in Atlanta, Garrett experienced bouts of facial paralysis. “I just thought I had a crooked smile,’’ Garrett said.

But then, as she was starting her sophomore year at Rhodes College in Memphis five years ago, she noticed a small, painful protrusion on her shin. Tests ultimately revealed that the bump on her leg was a harbinger of the genetic ailment already spawning tumors inside her brain. One night, prowling the Internet for details, Garrett discovered something that stunned her: Patients with the tumors frequently lose their hearing. “I called and I asked my mom, ‘Am I going to go deaf?’ And she said, ‘We just don’t know.’ ’’

Without realizing it, Garrett had already lost hearing in her right ear. She had begun, unconsciously, compensating for that deficit, something doctors have witnessed in other patients. When she strolled into a classroom, she later realized, she would veer toward desks on the right side - so that her left ear could hear the instructor. When her cellphone jangled, she would always put it to her left ear.

In the language of doctors, the tumors caused by the condition are considered benign, because their cells lack the capacity to rapidly and destructively divide, a key trait of malignant cancers. But the complications that can result from neurofibromatosis are anything but benign. “NF-2 is a disorder that’s like fighting a forest fire,’’ said Dr. Dade Lunsford, a University of Pittsburgh Medical Center neurosurgeon. “What you try to do is put out the fire that’s burning at that moment. So if there’s a hearing nerve tumor that’s getting bigger and causing pressure on the brain, normally we try to do surgery.’’

But both surgery and radiation can exact a toll. Operations on patients with tumors as large as limes - like those enmeshed with Garrett’s hearing nerves - almost always result in deafness. And while radiation can stop tumors from growing, it can spur scarring and may cause cancer. That is why researchers had long been eager to find some other way to tame the tumors. Traditional chemotherapy seemed unlikely to help because it targets those rapidly dividing cells that aren’t found in benign growths.

Newer drugs, pioneered by Boston scientists, aim at a different pathway, known as angiogenesis. Those medications starve cancerous tumors of the blood they need by disrupting blood vessels spawned by the tumor. But it wasn’t clear - until now - that the benign tumors of neurofibromatosis type 2 patients had the ability to grow those vessel networks.

By using old tissue samples, the Mass. General researchers showed that the tumors are indeed associated with excess blood vessel development. So the scientists decided to give 10 patients Avastin, one of the new class of angiogenesis inhibitors.

Garrett’s hearing declined precipitously in December 2006; before taking the medication, she scored 8 percent on a standard hearing test known as word recognition. Now, she stands at 98 percent in one ear, but still lacks hearing in the other. “You’re lucky as a physician,’’ Plotkin said, “to see a response like this once in your career.’’

Of the 10 patients in the study, the tumors of six shrank by 20 percent or more, with the reduction lasting 11 to 16 months so far. Seven patients had hearing loss prior to treatment, and after taking Avastin, the hearing of six either improved or remained stable. The patients experienced some side effects from the drug, including high blood pressure and liver toxicity, but none was considered severe.

Lunsford, who was not involved in the research, described the findings as “extraordinarily preliminary data,’’ but added that the study “offers a glimmer of hope, and it certainly warrants further exploration.’’

It remains unclear, for example, whether patients would need to take the drug regularly or if they could stop and start. The Boston scientists are looking for financing to expand their research to other centers.

Garrett isn’t taking Avastin at the moment because she underwent surgery in June designed to ease her facial paralysis. Still, she’s well enough that she’s preparing to start a new job. In the fall, she will begin teaching high school math in Atlanta - at a school for hearing-impaired children.


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